1. Field of the Invention
This invention relates to an information recording apparatus which records video information or audio information through the rendition of variable-length encoding.
2. Description of the Prior Art
Video information is a huge amount of data, and therefore when it is transmitted or recorded, it is often rendered high-efficiency encoding in order to reduce the quantity of data. The high-efficiency encoding is a means of compressing the quantity of data by eliminating redundant components possessed by video information. A specific scheme of high-efficiency encoding is to divide input sampled values into blocks of adjoining pixels and encode individual blocks through the orthogonal transformation. Orthogonal components are rendered quantization and variable-length encoding for transmission.
The variable-length encoding is to encode a signal with a lower occurrence probability into a coded word of a large number of bits and encode a signal with a higher occurrence probability into a coded word of a less number of bits, thereby transmitting data in a less number of bits as the whole. Conventional transmission and recording apparatus dealing with video or audio data are based on the variable-length encoding scheme, such as that mentioned above, for the reduction of data in carrying out their inherent roles.
However, with variable-length encoding being used, even a single-bit error incurs disorder of synchronous encoding, disabling the variable-length coded signal from subsequent decoding. On this account, the conventional apparatus are very vulnerable to errors of transmission path, and they need many error correction codes and reset signals for the protection of data.
The present invention is intended to overcome the foregoing deficiency of the conventional recording and playback apparatus.